An Improved Parallel Thinning Algorithm

One recent parallel thinning algorithm is analyzed on detail in this paper.The analytical emphasis is put on its pixel deletion conditions.It is shown that owing to the inherent faults in these conditions,not only all four elements of an isolated 2x2 square are removed but also there exist "worm eaten" response and "thin hair" phenomina in its result skeleton.Subsequently,an improved one is proposed which is also strictly 8 connected.Experiments indicate that the modification effectively overcomes the original's shortages and has a little better time efficiency.     

MCPB-ethyl对富士苹果疏花效果的研究

探讨了MCPB-ethyl的喷布时期、喷布浓度对富士苹果的疏花效果、果实发育和果实品质的影响。试验证明,MCPB-ethyl是一个良好的苹果疏花剂,有效喷布期是中心花盛开后1～5d,最适喷布期是中心花盛开后1～3d;最适喷布浓度为15mol／L,对果实发育、果形、果实着色和果实品质无不利影响。     

不同抚育强度对华北落叶松生长量的影响

为了探求不同密度株数对华北落叶松的影响,通过抚育管理提高华北落叶松年生长量,采用标准地平均生长量对比的方法研究了不同抚育强度对24年生华北落叶松胸径、树高和材积年生长量的影响。结果表明,不同抚育强度对华北落叶松胸径与材积的年生长量有显著影响,随着抚育强度的增大,胸径、材积年生长量逐渐增加,当抚育强度为450株/hm2时,胸径和材积年生长量达到最大值;而抚育强度对其树高无显著影响。     

A Fast Median Filtering Algorithm

A fast median filtering algorithm basing on the coherence of data in adjacent windows is presented.During median filtering,only the first median value is found by conventional squencing algorithm,the other median values are obtained by bisecting search method and quickinserting new element in sequenced window.For convenience of moving filter window along signal data,a data structure is desinged,which can make the new input element to cover output element and greatly reduce the quantity of computation.A 2-dimensional fast median filtering method by moving filter window along snack path is also introduced.     

精量播种减免间定苗对棉花产量和产量构成因素的影响

间苗、定苗是黄河流域棉区十分普及却费工费时的棉田管理措施。通过精量播种减免间苗、定苗环节,将为黄河流域棉区棉花轻简化栽培提供新的技术途径。2011-2013年连续3年在山东省临清市、夏津县、惠民县和东营市4个地点,以常规播种保苗方式为对照,研究了精量播种保苗(播量11.25 kg hm–2,出苗放苗后不间苗、定苗)方式对棉花收获密度、籽棉产量和产量构成因素的影响。年份、地点和播种保苗方式对棉花收获密度、籽棉产量和铃数皆有显著的互作效应。12个点次(3年4个地点)中有10个点次精量播种保苗方式的收获密度达到4.5~8.5株 m–2,铃数和籽棉产量与常规播种保苗方式相当;2011年东营点和2012年惠民点精量播种保苗方式的密度分别只有3.53株 m–2和3.63株 m–2, 铃数比常规播种分别减少13.8%和9.7%,单铃重与各自的对照无显著差异,籽棉产量分别减少14.2%和5.5%。精量播种处理中2个点次减产的主要原因在于收获密度过低,导致铃数降低。通过提高播种质量确保较高的收获密度,精量播种减免间定苗能够实现省工节本不减产,可作为一项重要的简化栽培措施在黄河流域棉区推行。     

苹果郁闭园不同间伐方式对果树群体结构和果实品质的影响

以成龄‘红富士’苹果郁闭园为试材,设计隔行间伐（处理A）、隔株间伐（处理B）、行内隔3去1间伐（处理C）3种处理和对照(CK),研究它们对果树群体结构和果实品质的影响。结果表明：与对照相比,各间伐处理的枝类组成得到了不同程度的优化,叶丛枝、短枝和长枝比例增加,徒长枝比例减小;3个处理的每公顷的总枝量、树冠覆盖率开始时下降明显,以后逐年恢复;处理A的行间交接率明显下降,而处理B的株间交接率下降明显;各处理的叶面积系数降低,叶片变大,百叶厚度增加;果园的通透条件明显改善。间伐处理的果实外观品质如单果重、色泽、着色面积、优质果率均明显的好于对照;果实的内在品质如含糖量增加、滴定酸含量下降、硬度增大,果实的风味和质地等也都优于对照。试验得出结论,适宜的间伐方式可从根本上改善苹果郁闭园的群体结构,提高果实品质,各间伐处理的综合效果以处理B最佳,处理A次之。     

施肥与疏枝定苗对鲜食蚕豆产量及其农艺性状的影响

为明确黑地膜覆盖栽培方式下,施肥和疏枝对鲜食蚕豆产量及其农艺性状的影响,以大粒型鲜食蚕豆品种‘慈蚕一号’为材料,于2015—2016年在浙江省杭州市余杭区进行了肥料和疏枝二因素裂区试验。结果表明:肥力相对比较低的处理,疏枝比不疏枝处理产量降低,随着肥力水平的增加,疏枝处理的产量高于不疏枝处理。疏枝处理能提高蚕豆商品性。建议低肥力水平下不进行疏枝处理,在高肥力水平条件下,进行疏枝处理。从节本考虑,在适宜的密度条件下,控制施肥量,不疏枝也能达到较高的产量;而从提高商品性出发,用疏枝处理的方法,则能提高3粒荚的比例。本试验中,在每公顷27000株的密度下,用黑地膜覆盖栽培法,每公顷施基肥复合肥450 kg、钙镁磷肥450 kg、追肥复合肥225 kg、硫酸钾15 kg,疏枝处理,产量最高达17787.70 kg/hm~2;每公顷基肥复合肥450 kg、钙镁磷肥450 kg、追肥尿素75 kg、硫酸钾15 kg,不疏枝处理,产量达17692.40 kg/hm~2;两者无显著差异。     

光皮桦天然林分生长与结构对间伐强度的响应

针对光皮桦天然次生林分抚育经营管理技术薄弱、林分生产力低的问题,开展光皮桦天然次生林不同强度的抚育间伐试验,旨在掌握抚育间伐对其生长的影响。在光皮桦天然次生林内,设置0%(CK)、10%、20%和30% 4个间伐强度,分析不同间伐强度对林分的胸径、树高、单株材积、蓄积等林分生长及直径分布特征、空间优势度等林分结构的影响。结果表明:（1）在间伐强度≤30%时,光皮桦林分平均胸径、树高、单株材积与蓄积的生长量随间伐强度增加而增加。其中30%强度间伐对林分生长最显著,分别高于CK林分133.0%、67.6%、67.3%、89.5%。（2）间伐有利于林木向大径级发展,随间伐强度的增加,林分胸径在4~10 cm的林木所占比例低于CK林分2.46、8.19、13.69个百分点;间伐显著改善林分空间优势度,其中,30%间伐强度最高为0.366。在光皮桦次生林经营管理过程中,基于改善林分结构,促进林分生长,对平均年龄为13年、林木密度为2500~2900株/hm²的光皮桦次生林林分建议采用30%间伐强度。     

露地简约化栽培甜瓜的不同留果方式对产量及品质影响

为探讨露地简约化栽培甜瓜不同留瓜方式对甜瓜干物质量、产量及品质的影响,在露地简约化栽培条件下,以‘黄皮9818’为供试品种,分别设置单株留2果、留3果和任意结果3种留果处理,比较分析成熟期不同留果方式下干物质量、果实特性及产量品质的差异。研究表明,3种留果方式下植株的干物质、果实特性及产量品质间存在一定差异,各处理干物质积累量表现为T（3887.1g/株）＞T2（860.2g/株）＞T（1771.2g/株）,且T2、T3处理与T1处理达显著差异,2次采收期T1处理折光糖含量均高于T2、T3处理。综合丰产性和经济效益,任意结瓜(T3)处理可获得较高的产量31200kg/hm²,其经济收益为62400元/hm²。     

A New Fast Algorithm for the Discrete Cosine Transform

We prepose a new fast algorithm for computing discrete cosine transform and its inverse on two dimensional input sizes which are powers of 2.Because the integer operation is more faster than the float operation in computer,the integer operation is used in this algorithm.Through the matrix linear transform the number of operation for multiplications and additions is reduced,so that the speed is greatly raised.This algorithm is applied to our developmented JPEG image coding,and yields very good results.     

平衡式疏果修剪法对龙眼生长与结果的影响

为探明幼果期疏果结合修剪对龙眼植株生长和结果的影响,选用6 年生‘石硖’幼年结果树为试材,以回缩修剪、初始结果枝率、初始单穗果数为试验因素,采用L9(34)正交设计,研究不同试验因素对果实成熟时的新梢比率、落果速率、结果枝率、单穗果数、产量、成熟期和果实品质的影响,并初步筛选出优势因素与水平组合。结果表明：经过疏果修剪的各处理植株在枝梢生长、果实发育和成熟品质上,都与对照有着明显差异,表现为落果率降低(P<0.01),成熟期提前,有一定的新梢比率,且合适的处理有助于提高植株单位产量;单果重增加,果肉TSS含量提高,果色偏向干净、明艳的黄绿色(P<0.01)。初始结果枝率越高的处理,成熟时果枝比率越高;回缩修剪植株的果实外观色泽比不修剪的偏向饱和黄绿色;初始单穗果数越高的处理,果实发育越慢、落果速率越高、成熟时单穗果数越多、成熟期也越晚;单穗果数处于中间水平60 粒的处理,单果重和TSS含量最高(P<0.01)。正交试验方差分析结果显示,成熟时单穗果数在因素初始单穗果数、果表h°值在因素矮化修剪的不同水平上存在显著差异(P<0.05);直观分析结果显示,结果枝率50%~60%、单穗果数60 粒左右,适度的回缩修剪,是龙眼植株获取生长与结果、产量与品质平衡关系的最优组合。该技术为生产应用提供了可行的操作指导。     

基于目标树中心样圆法的华北落叶松天然林抚育间伐生长效应研究

为探究抚育间伐对华北落叶松天然林生长效应的影响,利用目标树中心样圆法,对关帝林区1998年之前进行过不同抚育间伐强度处理的华北落叶松天然林进行实地调查,发现随着抚育间伐强度的增强,华北落叶松单木材积和生物量增加,但不同间伐强度无显著差异。抚育间伐对林分总的材积和生物量有明显影响,重度间伐会造成林分材积和生物量的显著减少。中重度抚育间伐会显著促进华北落叶松单木胸径的增长。采取中度间伐可以促进林分总生物量的增加,而为了大径材的生产可以采用重度抚育间伐措施。     

Fast Algorithm of Loads Equalization for Distribution Networks Based on Partition-hierarchical Model

Along with enlargement of scope of distribution, algorithms of reconfiguration for distribution networks become difficult to satisfy real-time require of engineering applications. This paper provides a new algorithm a fast algorithm based on partition-hierarchical model. It is found that partition of loads is relation of the smallest load of vertex that is bigger than average and the biggest load of vertex that is smaller than average. The method reduces the numbers of switches combination by searching smallest load of vertex that is bigger than average and the biggest load of vertex that is smaller than average and realize a fast algorithm of the loads global optimal equalization for distribution networks by transferring the loads. Results of test show that the method presented is applicable and efficient.     

A Class of Hypergraphs with the Best Connectivity

A jumping sequence is proposed,so that a class of r-uniform hypergraphs with nvenices and n edges is constructed. Then by analysing the connectivity of its two-section (graph),this class of hypergraphs is proved to have the best connectivity. The class of hypergraphs can beused to desisn the optimal fault-tolerant multibus computer systems.     

An Image Reconstruction Fast Algorithm Based on Orthogonal Wavelets Derived from Symmetric Scale Functions

A new image reconstruction algorithm is presented, based on orthogonal wavelets derived from symmetric scale functions. The analysis and practice show that the method lessens greatly the computational time,and improves the reconstruction quality.     

Fast Algorithm About Unit Commitment Based on Revised BP Artificial Neural Network and Dynamic Search

In order to reduce the operation cost and optimize the unit commitment,the fast algorithm about unit commitment based on revised BP ANN(Artificial Neural Network) and dynamic search is discussed.The BP ANN is trained with Levenberg-Marquardt algorithm,which aiming at its drawback of the storage of some matrices that can be quite large for certain problems,and a revised algorithm is presented.The BP ANN is used to generate a pre-schedule according to the input load profile.Then the dynamic search is performed some stages where the commitment states of some of the units are not certain.The experimental results indicate that the proposed algorithm can reduce the execution time and memory space without degrading the quality of the generation schedule.     

A Practicable Engineering Algorithm ofParallel Machining System

Parallel machining system is a kind of typical production environment.Its scheduling algorithm has Np_Completeness if E/T is optimal criterion.In this paper,an advanced heuristic algorithm is developed.The new algorithm's property lies in simplified computation,low complexity and easy programming.It has been shown that the heuristicalgorithm can be used in engineering.     

A Survey of Power Flow Tracing Algorithm

Competition in the electricity markets requires identifying the responsibility in the use of transmission networks or the associated effects. Power Flow Tracing algorithms have been developed recently to enhance the transparence of transmission system. This paper focuses on power flow tracing procedures and provides a detailed comparison of three classified algorithms: 1) power flow tracing based methods; 2) current tracing based methods; and 3) power flow analytic methods. The advantage and disadvantage of each method are discussed. Finally, the potential applications and development of the methodology is presented for furthermore research.